Permutation lock



" F. L. GRAHLFS PERMUTATION LOCK May 20 1924. 1,494,418

Filed sent. 20. 1919 s Sheets-Sheet 1' WWW - May 20, 1-924.

, amen toe [hands L. Grab/f5 @331 5/15 mom M24? Patented ill/lay 2t), 1924.

nniran STATES FRANCIS L. GBAHLFS, OF BROOKLYN, NEW YORK.

rnnivrtr'rerron LOCK.

Application filed September 20, 1919. Serial No. 325,100.

To all whom it may concern:

Be it known that I, FRANCIS L. GnAi-ILFs, a citizen of the United States, residing in the city of New York, borough of Brooklyn, county of Kings, and State. of New York, have invented a certain new and useful Permutation Look, of which the following is a specification.

This invention is a doors and the like and is of thec-haraeter whereby a door may be maintained in locked 1 condition, but may be opened from without, without the use of keys by such persons as are familiar with the combination ofwthe only, and not as defining the limits oif tlie invention. i 1

Figure 1 is a vertical section through a door on which is installed the lock embody: ing the present invention, a section being taken in the line 1-1 of Figure 1. 1

Figures 2 and 3 are detailed views of: elements of construction employed in the lock.

Figure l is a view taken from the inside of the door showing the cover plate and the inside knob removed.

Figure 5 is a detail of another element of the construction; and

Figure 6 is a wiring diagram of the device. Referring to the drawings 1 indicates the door on which the lock is shown as installed. The major portion of the operating parts of the lock is housed in and carried by the box like casing 2 which is let in to the inner face of the door as shown in Figure 1 and is secured in place by screws 3 as shown in Figure 1. Inner and outer door knobs i and 5, respectively. are associated with the lock, the stem 6 of the outer knob being journalled permutation lock for but the construction therein shown is to be understood as illustrative for rotation in a bushing 7, passing substantially half-way through the door, while the inner end of said stein carries the gear wheel 8. The stem 9 of the inner knob 4. is

iournalled for rotation in an inside cover plate 10 by means of a bushing 11, is precluded from withdrawal by a collar 12, and has a squared portion 18.. The inner end of the stem 9 is. in the form of a cylindrical pin Mwhicli seats in a pocket in the end of the stem 6 and by this engagei'i'ieiit the stems of the inner andouter knobs l and are maintained in co-axlal alinement but are free for independent rotation.v The inside cover plate '10 is adapted to. be normally secured in place by means ofscrews 15 which thread into interiorlythreaded lugs 16 on the box like casingQ, but this cover plate adapted to be removed at any time. from the inside of the doorforthe purpose of exam 111111;; or changing the operating parts of thel ock housed within said casing.

lllounted for sliding movement on the box like casing 9. is the bolt 17 of the lock which is normally maintained in shunt position by means of a coiled spring 18 surrounding its stem 19 as shown in Figure 4.

The inner end of the steam is shaped in the formof a yoke QOnormally in engagement with the u rock plate 21 .mounted on the. squared portion 13 of the stem 9 to which the inner knob 4; is attached. Through tlieina- 'nipulationfl of the inner knob the rock plate 21 may be oscillated in either direction to exert a pull upon the yoke 20 with the re.

suit that the bolt 17 is retracted to allow oi? the opening of the door from within with. out necessitating the use of keys or any other thorized person who is aware of the combination of the lock. The stem 6 of the out-- side knobis mounted for free rotation and the gear 8 which it carries while intended as a prime mover for the bolt is normally free from engagement with the operating connections sothat the knob 5 may normally be turned freely without having any effect whatsoever uponthe bolt; It is adapted lltl extends rearwardly of the push buttons back into the interior of the box-like casing 2, and around each of these stems is coiled a helical spring 25, serving to normally project the push buttons outwardly into operative posi tions.

The push buttons are preferably arranged in annular relation and co-axial with the annular series of buttons is a post 26 which is rigid with the base of the casing 2 and extends rearwardly in perpendicular relation thereto. Post 26 has a head 27 over which is fitted a cap 28 adapted for sliding movement on the post but normally forced into the rearward limit of its travel by spring 29 housed within the cap. Pivoted for oscillation on a fulcrum 30, supported on a suitable bracket, not shown, is a bell crank lever 31, one arm of which is secured by means of a link 32 to the cap 28 andthe other arm of which is secured by a link 33 to a rack 34. One end of the rack 34;, is pivoted to and carried by the bolt 17 of the lock as shown in Figure and a spring 35 normally exerts a slight downward pressure on the rack to take up lost motion. The spring L 29 which is housed within cap 28 normally serves to hold the bell crank lever at the backward limit of its travel and maintain the link 33 in raised position thereby holding the free end of the rack 34 free from the gear 8 carried by the stem of the outside knob 5. However, the bell crank is moved in a clockwise direction on its fulcrum 30.

A downward thrust will be placed on the link 33 which will force rack 34 into engagement with the gear 8, whereupon rotation o'fthe knob 5 will cause the bolt 17 to be actuated. This oscillation of the bell crank lever 31 is, in accordance with the present invention, dependent upon the pressing of one or more of the push buttons but, in the preferred embodiment of the invention, one push button is utilized to impart this movement to the bell crank while another is utilized to normally look the parts against such movement.

It is desirable, however, that the combination of the lock may be changed from time to time and accordingly a structure is shown which enables the employment of any two push buttons to carry out the functions described. To this end there is arranged coaxial with the post 26 a pair of bracket rings 36 and 37 of different diameters secured to the back of thebase of the casing and on each of these rings are formed which are adapted to be associated levers connecting any two push buttons with the portions of the lock associated with the post 26. The levers in question are shown in Figures 2, 3 and 5 in detail and their particular function and arrangement will now be described. The lever 40 shown in Figure 2 is bifurcated at one end to straddle the cap 28 and is provided with trunnions 41 which fit into apertures into the opposite sides of the cap to pivotally secure the parts together. The other end of the lever is also bifurcated to engage with one of the stems 24: of a push button and is perforated so that the cotter key or split pin may be passed through that end ofthe lever and the rear end of the stem 24 to pivotally secure these parts together. Intermediate its ends the lever 40 is provided with a pair of trunnions 4E2 adapted to engage with the apertures in the brackets 39. The lever 40 is moreover preferably split down its center to render it resilient in a transverse direction to facilitate the positioning of the trunnions in any particular pair of brackets 39 dependent on the particular push button with which the lever is to be associated. iVhen associated with push button 22. the parts are as shown in Figures 1 and 4, so that the pressing of the push button 22 has the function of transmitting power through the lever 40 to draw the cap 28 forward, oscillate the bell crank 31 and bring the rack 34; in engagement with its operating gear 8.

However, the ,operations described are normally precluded by means of a locking pawl 43, the function of which is to normally lock the cap 28 against forward move ment so as to preclude unauthorized persons from opening the door until the cap is unlocked by one who knows the combination of the lock. Locking pawl 43 as shown in detail in Figure 5 is provided with a pair of trunnions 44 and is bifurcated to allow of the positioning of these trunnions between any two adjacent perforated brackets 38 of the ring 36. It is also provided with a shoulder 45 which in normal position of the locking pawl engages with the forward edge of the cap 28 as shown in Figure 1 so as to lock the cap against forward movement. It will be noted that the locking pawl is in the general form of bell crank to one arm of which is pivoted a lever 46 shown in detail in Figure 3 and through the agency of which lever the pawl may be moved into and out of locking position. Lever 46 is split after the manner of the lever 40 and for like reasons and its trunnions 47 are adapted to co-operate with brackets 39 after the same manner as described with reference to the lever a0.

However, one of its ends is pivoted to looking pawl 43 while its other end is secured, preferably by a cotter key or split pin to the stem 24: of one of the push buttons, the arrangement being as shown in Figure 1. If the push button 22 is pressed, power will be transmitted from the lever 46 to the looking pawl 43 with the result that it will be moved in a clockwise direction out of the path of the cap 28 to allow of the movement of said cap under the impulse of the push button 22. While the operating and locking members are shown as associated with'push buttons 22 and 22", it will be manifest that" 1 they can be just as well associated with any other two buttons and may be so changed at any time'to change the combination of the lock.

From what has been said it will be manifest that it requires the pressing of both the ated with the lock, whereby tampering therewith will immediately makeitself known to the occupants of the house. This means'is preferably electric and now will be de-.

scribed. Rearwardly of the face plate 23, there is formed in the face of the door back of the push buttons a circular cavity 48, and in this cavity adjacent each push button is a contact 49 as clearly shown in Figures 1 and 6. Also mounted on the base of the cavity is a metallic ring 50 and each push button is provided at its base with a metallic washer 51. When any push button is pressed, it completes the circuit between one of the contacts 49 and the ring 50.

Positioned at some convenient place within the house is a bell or buzzer 52 included in a battery circuit 58 having its terminals in a pair of binding posts 54 and 55 mounted on the blocks of insulation 56 housed within the box-like casing 2, shown in Figure 1. From the binding post 54 wires extend to certain of the contacts 49 while from the binding post 55 other wires extend to the remaining contacts 49. The wiring connections are such that when the two buttons forming the combination of the lock are pressed no circuit will be completed through the bell or buzzer 52 and no alarm will be sounded, but if a person unfamiliar with the lock and not knowing its combination endeavors to tamper with it the bell will be sounded before he has attempted more than one or two combinations. Suppose, for example, that he presses the buttons 22 and 22. The pressing of the button 22 will complete the circuit from'the positive main to the ring 50 while the pressing of the button 22 will complete the circuit from the'ring 50 to the negative main and the bell will ring. In like manner, the pressing of the button-22 will complete the circuit from the positive main to the ring 50 and the pressing of the button 22 will complete the circuit from the ring 50 to the negative main and so on so that the bell will ring if any two buttons are pressed which will complete the circuit at the two points where it is normally broken. In this 'fingersof one hand the buttons 22 and 22 the pressure on the button 22 slightly pre- 1 ceding the pressure 011 the-button 22, by the first pressure the locking. pawl 43 ismoved out of the path of the cap 28, whilethe pressure on the button 22 forces the rack 34 downwardly into engagement'with the gear 8. With the other hand the operator turns 'the knob and the bolts start to move back. lVhen itis moved but a very short distance,

the free end of the rack 43 comes beneath a shoulder 57 projecting rearwardly from a base of the casing 2 and this shoulder serves to hold the rack in engagement with the gear 8 for the remainder of its backward travel so that the fingers may be now released from the push button and continued rotation of the cap fully retracts the bolt 17. As soon as the push buttons are released, the spring 25 associated' with push button 22 immediately retractsthe push button but the push button 22 is not retracted until the door is opened and the knob released. The spring 18 backofthe bolt then forces the bolt outwardly and the rack 34. follows until released from the shoulder57.whereupon the spring 29 housed in the cap 28, assisted by spring 25 back of the push button 22, lifts the link 33 and elevates the rack 34 into. its normal inoperative position shown in Figure 4. During this operation the bell or buzzer 52 remains inactive for the reason that a vi in mesh with the gear and-permit the operation of the bolt from the knob.

3. A permutation lock embodying an aotuating handle, a gear associated therewith, a'

locking bolt, a rack associated therewith, and normally maintained free from engagement with the gear of the actuating handle, means for normally locking the rack in a position tree from engagement with the gear and selective'push button mechanism fo-r releasing the rack for movement into engagement with the gear and for moving said rack into engagement with said gear to render the locking bolt responsive to the operations of the actuating handle.

4, A permutation lock embodying an actuating handle, a gear associated therewith, a locking bolt, a rack associated therewith and normally maintained tree from engagement with the gear to. render the locking bolt irresponsive to the operations of the actuating handle, means for locking the rack tree from engagement with the gear, a series of push buttons, connections between one of said push buttons and locking means for releasing the rank to allow of its movement into engagement with the gear, and connections between another push button and the rack for forcing it into and holding it in' engagement with the gear to render the lockingbolt responsive to the operations of the actuating handle.

5. A permutation lock embodying an actuating handle, a locking bolt normally irresponsive to the operations of the actuating handle, means for connecting the locking bolt to the actuating handle, a plurality of push buttons, and means for attaching the connecting means with any one of said push buttons whereby the operation of said attached button renders the locking bolt responsive to the operations of the actuating handle.

6. A permutation lock embodying an actuating handle, a gear associated with said handle, a locking bolt, a rack associated with said bolt, and normally free from engagement with the gear, a plurality of push buttons, andmeans for connecting any one of said push buttons to the rack whereby the operations of the push buttons to which the rack; is connected serve to bring the rack into engagement with the gear and render the bolt responsive to the operations of the actuating handle.

7. A permutation look embodying an actuating handle, a gear associated with said handle, a locking bolt, a rack associated with said bolt, and normally free from engagement with the gear, a plurality of push buttons, and means for connecting any one oi said push buttons to the raol: whereby the operations of the push buttons to which the rack is connected serve to bring the rack into I engagement with the gear and render the bolt responsive to the operations of the actuating handle, means for normally locking the rack against movement into engagement with the gear and means for connecting any one of the remaining push buttons to the locking means whereby the operation of said last mentioned push button releases the rack for movement into engagement with the gear.

In testimony whereof, I have signed my name to this specification.

FRANCIS L. GRAHLFS. 

